Cartridge-stop for rimless cartridges



IVI. H. BURST- GARTRIDGE STOP FOR RIMLESS CARTRIDGES.

(NO Mpdel.)

Patented Feb. 13, 1894.

I?? .ven for."

M H Durslj ma nnzcmu. um.; nnnnnnnnnn PAIN.

UNTTEn STATES aTnNT Trice.

CARTRIDGE-STOP FOR RIVLESS CARTRIDGES.

SPECIFICATION forming part of Letters P atent No. 514,451, dated February 13, 1894.

Application filed November 30, 1892. Serial No. 453,629- (No model-.l

To a/ZZ whom t may concern:

Be it known that I, MURRAY H. DURsr, a citizen of the United States,residingatIVheatland.,in the countyof Yuba and State of Californla, have invented certain new and useful Improvements in Breech-Loading Firearms, of which the following is a specification.

This invention relates to breech-loading fire-arms especially adapted for using the socalled rimless cartridges; the object being to provide means for properly locating the cartridge within the barrel prior to firing the same, for overcoming the transverse breakage of the shells. In the drawings accompanying and forming a part of this specification, Figure 1 is a sectional side elevation of a portion of a breech-loading gun embodying my present improvements. Fig. 2 is a plan View of the parts shown in Fig. 1. Fig. 3 is a transverse section in line a b, Fig. 1. Fig. 4 is a side View of the cartridge-stop. Fig. 5 is an end view of said stop.'

Similar characters designate like parts in all the figures.

It Willbe remembered that in using the socalled rim cartridges heretofore more generally employed, it has been customary to limit the entering movement of the cartridge into the chamber of the gun-barrel by means of the rim of the cartridge striking against the rearward end of the barrel, the cartridge being forced into the barrel by the bolt of the gun. According to that arrangement, of course, the cartridge is accurately located by the clamping of its rirn between the rearward end of the barrel and the forward end of the bolt, so that no space would exist, at the moment of firing, between the rearward face, or head, of the cartridge and the bolt. According to the old plan, therefore, the particular length of the cartridge, measured from the head thereof to the forward shoulder at the base of the projectile, was not important within moderate limits; nor could the firing-pin, when striking the cap, drive the cartridge forward in the barrel, since the rim of the cartridge positively limited the entering movement thereof. In using the rimless cartridges, however, since the diameter of the heads of the same is equal to or less than the diameter of the rearward end of the shell, it has been customary to rely upon the forward shoulder 3 of the cartridge coming against the corresponding face, or shoulder, of the barrel at 4, to prevent the cartridge from going' too far into the bore of the gun. In practice, it has not been found practicable to precisely locate the cartridge in the barrel by means of said shoulder, since the length between the rearward face 2 of the cartridge and its shoulder 3 varies by an appreciable amount, so that, accurately speaking, the rimless cartridges are ot' various lengths. Vhen the rimless cartridge is driven forward into the barrel, the obvious tendency of itis to go forward against the barrel-shoulder4; and if the cartridge is shorter than its normaler proper length, this willleave a corresponding space (not shown) between the head of the cartridge and the bolt. Also, the effect of the firing-pin, when this is thrown forward, is to drive the cartridge its full length into the barrel, therebyincreasing the space between the cartridge-head and the bolt to the maximum amount. If, now, the cartridge be fired, the first effect of the eX- plosion is to expand the shell within the barrel until this bears against the inner surface of the chamber with such a force that the pressure of the gases longitudinally of the shell, even afterthe bullet has been expelled,

is not sufficient to slide the shell back in the chamber, but throws the entire longitudinal force of the explosion into the shell at a point near the rearward end thereof. In practice, this enormous force is sufficient to tear asunder the cartridge-shell at about the line m, Fig. 1, leaving the forward portion 7 thereof in the barrel when the bolt is retracted, only the rearward portion '7 of the shell being extracted.

The object of my present invention is to provide means for limiting the entering movement of the cartridge into the barrel so that the head thereof will bear properly against the bolt at the moment of tiring; and to do this by means of a cartridge-stop operated by the bolt of the gun to positively engage the cartridge-head, and thereby locate the same with precision. v

The breech -loading bolt gun partially shown in this application has the usual bar'a rel, 6, which is bored or chambered at its rear- IOO ward end to receive the cartridge '7, and is fitted to be screwed into the forward end S of the receiver, or frame, 23, of the gun. Said frame is shown provided with a longitndinally-reciprocating bolt, which may be of any suitable and well-known construction. As herein shown, the boltconsists of the principal portion or part 9 having the forwardlyextending part 10 fitted to drive the cartridge into the bore of the gun and support the same when fired. The bolt-mechanism is shown provided with the usual firing-pin l1 actuated by a spring, 12, only partially herein shown.

In this application I have omitted to show Y the usual extractor, which is carried by the bolt and has its hook adapted for engaging in the recess, or groove, 14, forward of the head, l5, of the cartridge; this feature not constituting a part of my present invention, and being fully set forth in my aforesaid application.

For limiting the forward movement of the cartridge when this is driven into the bore of the barrel, I provide the fire-arm with a cartridge-stop operable transversely of the cartridge for engaging the same to limit the entering movement thereof. This stop, designated in a general way by 1G, is shown carried at the forward end of the stop-carrier, or lever, 47, which is shown supported on a pivot, 48, fixed in the frame of the gun. The stop 16 is shown fitting in anotch in the rearward end of the gun-barrel, and is adapted, by reason ofits being carried by the lever as aforesaid, to have a movement transversely of the cartridge for permitting the body of the cartridge-shell to pass the same and to engage in the groove, or recess, 14, forward of the head, 2, of the cartridge when this is driven into place as in Figs. 1 and 2. Vhen the cartridge is started into the barrel, the side of the shell, impinging against the inner end of said stop, drives this outward; and when the recess comes to the stop, this is thrown in radially by the stop-carrier to firmly engage the cartridgehead; this movement being effected by the cam, or stop-carrieractuator, 2l, that is carried by the bolt and acts upon the rearward end 49 of said lever 47. By means ofthe stopcarrier, and the cam movable with the bolt of the gun, for operating said carrier and stop, (the cam being located substantiallyas shown upon the bolt of the gun,) the action of the stop 16 is positive; and the cartridge-head 1s firmly gripped between the rearward face of said stop and the forward face of the bolt.

My present improvement in fire-arms has the same advantage as the improvement describedin my aforesaid application,in thatthe shoulder 4 of the barrel may be made somewhat in advance of the normal position of the shoulder 3 of the cartridge, leaving the space 3 for the disposal temporarily of any dirt which may be upon the cartridge-shells or which may be carried forward in the barrel on the insertion of the shell. On firing the gun, the pressure of gases within the shell expands the same to fill said space 3'; but this action of the shell does not ordinarily, in practice, burst the same or otherwise interfere with the extraction thereof.

Having thus described my invention, I claiml. In a breech-loading gun for using rimless cartridges, the combination with the barrel and means for delivering the cartridges thereto, of a cartridge-stop operable transversely of the cartridge for engaging the same to limit the entering movement thereof,a lever carrying said stop, and a cam carried by the bolt of the gun for operating the lever, substantially as described.

2. In a breech-loading gun for firing rimless cartridges, the combination with the barrel, of a stop-carrier provided with a stop operable transversely of the barrel for engaging the cartridge to limit the entering movement thereof, and a stop-carrier-actnator movable with the bolt of the gun for operating the carrier and stop, substantially as described.

3. In a breech-loading gun for using rimless cartridges, the combination with the barrel, of a cartridge-stop operable transversely of the barrel for engaging the cartridge to limit the entering movement thereof, and a longitudinally-reciprocating bolt adapted for delivering the cartridge into the barrel, and on its forward movement engaging the stop to bring the same into engagement with the cartridge, substantially as described.

MURRAY H. DURST.

Witnesses:

FRANCIS H. RICHARDS, WILLIAM G. RICHARDS. 

